package week07.data_obs3;

/**
 * Created by zhangxiaokun on 2018/3/13.
 */
public class SubjectTest {
    public static void main(String[] args) {
        ConcreteSubject subject = new ConcreteSubject();
        ConcreteObserver obs = new ConcreteObserver();

        subject.attach(obs);
        subject.change("Beijing");
        subject.change("Shenzheng");
        subject.change("Shanghai");
    }
}
